The colliery entrance survives in a cutting, probably scoured out during prospecting in the 1790s by the engineer and colliery entrepreneur Edward Martin of Swansea. The rock-cut tunnel, originally about 1.6km long and carrying a colliery railway and drainage channel, is blocked by a fall after about 60 metres from the entrance; thereafter it has been removed by open-cast mining. In the early 1820s the short colliery railway was adapted, probably by the engineer Joseph Jones of Ystradgynlais, as part of the Brecon Forest Tramroad (nprn 406399); this part of the scheme included a reworking of Gwaunclawdd Colliery.
RCAHMW, 09 February 2009.